Means for suspending and sealing casings



y 1951, H. ALLEN El AL 2,553,838.

means FOR susrsunmg AND smmp CASINGS F11! Doc. 4, 1948 Fig Herbert AllenMadden 7. War/rs //VVENTOR erg; 7% I ATTORNEYS Patented May 22, 1 951MEANS FOR SUSPENDING AND SEALING CASINGS Herbert Allen and Madden T.Works, Houston, Tex., assignors to Cameron Iron Works, Inc., Houston,Tex., a corporation of'Texas Application December 4, 1948, Serial No.63,497

Claims.

' This invention relates to improved means for suspending and sealing acasing or other pipe in a casing head.

One object of this invention is to provide a novel structure for hanginga string of casing at any point in its length within a casing head andsealing the casing to the casing head.

Another object of this invention is to provide a slip bowl havingdownwardly tapered outer and inner faces for respectively engaging thetapered bowl portion of a casing head and supporting a series of wedgeshaped slip segments by which the casing or other pipe is engaged. a

- A further object of this invention is to provide a slip bowl which inaddition to supporting theslip segments forms a part of the means'forseal ing the casing within the casing head.

. A further object of this invention is to provide slip suspending meansfor casing or other pipe wherein a divided ring of slip segments arepreliminarily attached to a slip bowl by threaded members and maintainedin widely spaced raised positions so as to facilitate assembly of themeans upon the pipe.

A further object of the invention is to provide a casing suspension andseal apparatus for a cas- .initial closure to permit removal of thecontrol equipment, after which a second seal may be established.

Other objects and advantages will be apparent from the followingdescription taken in connection with the accompanying drawingillustrating a presently preferred embodiment of this invention.

In the drawings:

The single figure is a vertical sectional view showing a string of pipesuspended in its supporting structure with suitable seals in placethereabout.

Referring now to the drawing, the numeral l0 designates a casing head,supported conventionally upon the surface casing (not shown) or otherpipe, and provided centrally with an inclined bowl portion H below acylindrical bore portion 2 of relatively large diameter. The upper endof the casing head H) is formed with a lateral flange l3 provided with aplurality of openings through which it may be bolted to the flange l4 ofan upper well equipment member, such as an-' other casing head, blowoutpreventer valve, or the like. The facing sides of flanges l3 and I4 haveregistering grooves to receive the metal seal ring l5 which forms afluid tight seal between them.

A string of well casing or other pipe is suspended from casing head Inby the downwardly tapering wedge shaped slip segments whose inner facesare toothedto engage and support the casing l6 and whose outer taperingfaces engage the downwardly tapering inner periphery of the slip bowlI8. The lower portion of the outer periphery of the slip bowl I8 isdownwardly tap ered to fit the tapered bowl portion I of the casing headwhile the upper portion of its outer periphery is shaped as a cylinderand of a diameter to fit within the cylindrical portion |2 of the casinghead. The upper portion |8a of the slip bowl is also crowned on itsupper face to aid in the compression of the resilient packing ring I!)superposed thereon, serving as the lower gland ring in the main sealingor pack-off assembly in conjunction with packing ring I9 and the uppergland ring 20, which has a depending oppositely crowned lower surfacefor aid in properly compressing and expanding the resilient packing ringl9.

The means for manually compressing and expanding packing ring I9 isherein shown as comprising a series of headed screws 2| having theirheads countersunk into openings in upper gland ring 2|] and providedwith non-circular sockets for the reception of a suitable wrench. Theshanks of screws 2| extend through aligned openings in the upper glandring 20 and packing ring [9 into threaded apertures in the lower glandring, herein shown as the upper portion I811 of the slip bowl l8. Screws2| are tightened down progressively to compress the resilient packingring l9 and expand it transversely of the axis of the casing to formseals between the casing l6 and the cylindrical portion l2 of the casinghead.

Additional seals may also be provided between the slip bowl l8 and boththe casing l6 and the casing head, or either of them, in order to forman initial seal between the casing head and casing before the screws 2|are tightened. In the illustrated embodiment, a seal is provided betweenthe tapered outer periphery of the slip bowl l8 and the bowl portion llof the casing head by providing an annular recess |8b in the slip bowlfor the reception of suitable resilient packing ring 22, as, forexample, a conventional O-ring. As the slip bowl I8 is lowered intoengagement with the bowl portion ll of the casing head, packing ring 22will be compressed to form a seal therebetweenv Between the casing isand the upper portion [8a of the slip bowl is arranged a. second seal23, herein. shown as a lip seal of suitable resilient material fittingwithin a conformably shaped annular recess I80 in the lower corner ofthe inner peripheral wall of the upper portion I811 of the slip bowl.The lip ring 23 is preferably formed with a divided skirt' portionarranged to be spread by fluid under pressure from the well intosealing, engagement with the casing l6.

Preparatory to mounting the slip bowl and slip segments as an assemblyaround casing 15, each slip segment H is secured to the lower taperedportion of slip bowl is in raised and retracted position by a suitablescrew (not shown) extending through. a suitable aperture ltd. in theslipbowl. andv threaded into a then aligned. threaded. aperture Ila in.the slip segment. The several slip. segments ll may also be maintainedall on. the. same level at all times by an outwardly expanding splitresilient snap ring 25 arranged in recesses. llb formed in the toothedinner faces. of the slip segments. With the. slip segments heldretracted by the bolts as described, the casingv may bereadilymanipulated to the point where it is to be hung. Then said bolts areremoved, permittingthe slip segments. to. advance with the. slip bowl itinto contact with the casing and the. entire: assembly is lowered intothe casing head it untilv the. slip bowl i8 seats. in the tapered bowll! of. the; casing head. Thereupon casing 56- is properly secured in.suspended relation from the casing, head. ring 25 is sufficient. topermit movements of the several slip-segments i'i relatively toeachother out of their. original aligned positions while serving to aid inkeeping: them on a. level with each other. At this point it will benoted that an initial seal will have been formed between. the casing andeasing head by means of rings 22 and 23 to prevent blowout of pressurewithin the annulus about the casing.

The suspension a-nd seal assembly are of such outside diameter as willpass downwardly through the bore of conventional blowout preventer andcontrol equipment which is usually used during the drilling and casingsetting operations.

After the casing is set and the seals are installed andtested, ifdesired, the control equipment may be replaced with other equipment,such as a tubing head, having a reduced bore as illus'- tratedin thedrawing.

l After the slip segments ii and slip bowl. l3 have reached theirpositions with the casing 55: suspended therein, packing ring I9 isadvanced over the upper end of the casing to rest on the crowned upperface of slip bowl portion l-Ba and the upper gland ring 20 similarlyadvanced to" rest on packing ring I8 Headed screws 2i are then threadedinto position and progressively tightened down to expand packing ring I9into sealing engagement with both the casing H and. the cylindrical boreportion 12 of the casing head. The seals may be tested, if desired,by'appmpri'atc testing apparatus before the well is completed,

While the illustrated embodiment is believed. to adequately fulfill theobject and advantages herein stated, it is to be understood that thisinvention is susceptible to modification and variation within the scopeof the subjoined claims.

Having described our invention, we claim: 1. In. combination with acasing head having The flexibility of the resilient snap:

4 a tapered bowl portion and a cylindrical bore portion thereabove,means for suspending and sealing a string of casing therein comprising aslip bowl having inner and outer tapered walls and adapted; to fitwith-inthe bowl portion of the casing head, a seriesv of slipv segmentsarranged to cooperate with the inner tapered wall of said slip bowl insuspending the casing, removable means for preliminarily supporting saidslip segments in raised positions within said slip bowl, .and means forsealing between the casing and casing head above said slip ringcomprising a lowerg-land ring. carried by said slip bowl, a resilientpackin ring, and an upper gland ring, headed screws threaded into one ofsaid gland rings being arranged to compress said packing ring and expandit into sealing engagement with both the casing and easing head. f

i 2. In combination: with aca-sing head; having a tapered bowl portionand a cylindrical bore. portion thereabove, means for suspending andsealing a string of casing therein comprisin a slip bowlhaving inner.and outer tapered walls and adapted to fit within the bowl portion ofthe casing head, a series of slip: segments ar.--- ranged to cooperatewith the inner tapered wall of said slip bowl in suspending the casing,means for preliminarily supporting said slip segments in.

raised positions within said slip bowl, packing" means carried by the.slip bowl for sealing itsouter taperedwal-l against the bowl portion,and packing means carried by the slip bowl for sealing its inner wallagainst thecasing', and means for sealing between the casing and casinghead above saidslip segmentsccmprising' a lower gland ring carried bysaid slipbowl, a resilient; packing ring, and an upper gland ring,headed screwsthreaded into one of said land rings being arranged tocompress said packing rin and expand it into sealing engagement. withboth the casing and easing head.

3. A well casing support and packofi assembly comprising a slip bowladapted to: be received by a casing head having a tapered seat with acylindrical portion thereabove', the upper'portion of the slip bowlbeing annular and of a dimension to substantially fill the space betweena well casing and a casing head, the upper annular sur face of the slipbowl providing a. seat, a packing ringon said seat, a packin gland onsaid ring, and connection means between said gland and slip bowl whichmay be tightened to advance the gland toward the slip bowl to expand thepacksure diil'erential to be sealed against.

HERBERT ALLEN. MADDEN T. WORKS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

